The goal of this project is to write a new software package to process data for Protein Crystallography collected with the fine slice method. In this method, each frame of x-raydiffraction is collected with the crystal rotated by a very small angle, for example 0.l degrees(or smaller).This is to contrast with the standard rotation method where the crystal would rotate by a larger angle in the range of l degree per frame. The fine slice method would yield a better quality data since it would have the smallest amount of background falling on top of each reflection. However, the software will be much more complex since each reflection intensity will be spread out in many frames (it would only be spread out to l or 2 frames in a standard rotation method?. The new package is loosely based on the old UCSD software package that was written to process data from the Multiwire Area Detector. However many improvements have been added. For example, the spot detection now use the skewness method which is completely unbiased. There is also a much better prediction for the width (in the data collection omega angle) of the reflections and a profile fitting of the curve "spot intensity" versus "data collection angle": omega. Some parts of the software has been written with very encouraging preliminary results. This new software will enhance the protein crystallography data quality which will result in better three dimensional structure of proteins. These structures are now so important because they are used not only to farther understand Molecular Biology but also to rationally design new drugs. New HIV protease inhibitors which now can control AIDs disease in most patients are the testimonies of the success of this drug design method. PROPOSED COMMERCIAL APPLICATIONS: Small market but product really needed by protein crystallography community. It could greatly help in drug design procedure.